Name: ____________________________________________ Date: _________________ Class: ______________
Water Remediation Lab Worksheet
Earlier we talked about how contaminants and pollutants enter groundwater. We also
talked about how engineers design ways to clean groundwater and make it safe to
drink. Running water through activated carbon, like in the picture below, adsorbs
contaminants and allows clean water to pass through.
Activated carbon block and powder photo source: 2006 Ravedave,
Wikimedia Commons,
http://commons.wikimedia.org/wiki/File:Activated_Carbon.jpg
Activated carbon pores drawing source: Innofresh Products, Inc.,
http://www.capitalcarbon.in/process.html
In this lab, we are going to test to see how well Brita® household water filters which
use activated carbon, remove chlorine from bleach water. Chlorine is used as a
disinfectant in treating drinking water, but too much chlorine in drinking water is
dangerous—it damages your nervous system and may cause cancer.
Water Remediation Lab activity –— Worksheet
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Procedure
1. Prepare the chlorine-contaminated water by adding a certain volume (refer to the
table, below) of bleach to the beaker containing 1 L of tap water. Record the
chlorine concentration tested at your lab station: ______________________
2. Once the sample chlorine-water is made, use a chlorine strip to test the starting
concentration of the contaminated water. Do this by pouring a small sample of the
beaker water into a paper cup. Dip the test strip in the water sample and then
compare the test strip to the scale provided in the test strip vial to determine the
chlorine concentration. Record the chlorine concentration in the worksheet table—
this is the measurement corresponding to time 0.
IMPORTANT: Never reuse a paper cup or test strip; always use a new paper cup
and test strip for each sample.
3. Pour the chlorinated water into the opening at the top of the Brita filter lid to
begin collecting it in the pitcher base. If the full liter of chlorine solution does not
fit, then just add enough of the solution so that the top reservoir of the water
pitcher (containing the solution to be filtered) is full. Add the rest of the solution
when enough room frees up.
4. Two minutes after the chlorine-contaminated water has started passing through
the filter to be collected in the pitcher base, use another chlorine strip to test the
concentration of the water. Do this by pouring a small sample of the filtered
solution in the base of the Brita pitcher into a paper cup and taking a chlorine
measurement, just as in step 4. Record the results in the worksheet table.
Water Remediation Lab activity –— Worksheet
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5. Every two minutes, pour another small sample of filtered water into a new paper
cup and use a new chlorine strip to test the concentration. Record the
concentrations in the table after each sample. Take measurements for 30 minutes.
6. After data collection is complete, graph the chlorine concentration vs. time to see
the adsorption pattern.
7. Once the graph is complete, pour water straight from a tap into a paper cup. Use
a chlorine strip to measure the concentration of the chlorine.
Record this measurement: ____________________
8. Leave the chlorinated solutions at your station for your instructor to dispose of.
Data Collection
Time (minutes)
Chlorine Concentration (ppm)
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
Water Remediation Lab activity –— Worksheet
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Data Analysis
Graph your data (from the table, above) on the graph, below.
Make sure to correctly label the x- and y-axes.
Water Remediation Lab activity –— Worksheet
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Questions
1. How well did the activated carbon water filter remove the chlorine?
Look at your graph for help and include data values in your answer.
2. The amount of chlorine in drinking water set forth by the Environmental
Protection Agency is 4 parts per million. Was the “contaminated water” you tested
safe to drink before filtration? After filtration? Is our tap water safe to drink?
Explain your answers.
Water Remediation Lab activity –— Worksheet
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